Control for a plurality of electrical consumers of a motor vehicle

ABSTRACT

A controller for a plurality of electric loads of a motor vehicle has a simple design and flexible applicability and expandability. Each electric load is arranged together with a local computer in a load module and is controlled by the respective local computer within the load module and the local computers are connected to a central computer over a databus and exchange control data according to a standard protocol.

FIELD OF THE INVENTION

The present invention relates to of automotive electronics or electricalsystems. More particularly, the present invention relates to acontroller for a plurality of electric loads in a motor vehicle.

BACKGROUND INFORMATION

Switching and/or controlling electric loads in a motor vehicle areconventionally performed with the use of simple switches (example: lighton/off), pushbuttons (example: power windows or electrically adjustableside mirrors) or actuators (example: instrument lighting) in an electriccircuit. The actuators are usually designed as analog devices. They arealso designed specifically for a given process or load and they arearranged in a decentralized location. This also has the disadvantagethat in the case of a plurality of electric loads, such as those in thecase of modern vehicles, there must also be a plurality of power supplylines with plug connectors leading from the switches, pushbuttons andactuators to the individual loads.

In addition, there have also been attempts to use a computer to controlsome of the electric equipment of the motor vehicle. The computer isarranged centrally and is designed in part specifically for the controlfunctions. It generates the control pulses for the electric component(the electric load). At the same time, the computer also performscertain “infotainment” functions, such as navigation, radio ortelematics. One problem is optimizing the operating system to performboth infotainment as well as control functions. However, retrofittingand scalability of functions from the control area are problematical ifhardware changes must be made in the PC.

German Published Patent Application No. 42 19 669 relates to a controlunit for calculating control quantities for recurring control operationsin a motor vehicle, including, in particular, engine management(ignition, injection) and the ABS brake system. The ignition module, theinjection module and the brake module each include a microprocessor, amemory module and on/off circuits, and these modules continuouslytransmit the control quantities achieved over a connected databus to acentral control unit. Any bus system suitable for data transmission inthe motor vehicle may be used for this purpose.

European Published Patent Application No. 392,411 relates to anautomotive controller having a central system manager module, whichworks together with load modules (air conditioner, power steering,transmission) over a bus. The system manager module, however, can beactivated only when the user has identified himself correctly as theproper user. No special transmission protocol is provided.

German Published Patent Application No. 44 01 785 describes anintegrated wiring system for a motor vehicle having a central controlunit and a plurality of terminal control units that exchange data. Thisdata exchange is not performed according to a standard protocol, butinstead according to different communication protocols at differenttransmission rates.

European Published Patent Application No. 307,344 describes anautomotive wiring system, in which user stations exchange data over abus. Interface devices are connected to the user stations in a starnetwork, with end devices (loads) connected in groups to the interfacedevices. There is no provision for combining them into load modules.

U.S. Pat. No. 5,732,074 describes a mobile portable wirelesscommunication system, in which data transfer occurs between a remotecomputer and an automotive controller according to the Internetprotocol. Data is converted in the motor vehicle and sent to a localcontrol network, which operates according to another bus system (CAN),not according to the Internet protocol.

SUMMARY OF THE INVENTION

Therefore, it is one object of the present invention to provide acontroller for the electric loads in a motor vehicle which has a simpledesign, can be adapted flexibly to a wide variety of control functionsand is easily scalable and expandable.

The above and other beneficial objects of the present invention areachieved by providing a controller in which each of the electric loadsis arranged together with a local computer in a load module and iscontrolled by the respective local computer within the load module, andthe local computers are connected to a central computer over a databusand exchange control data according to a standard protocol. An electriccomponent (load) which is to be controlled or switched is connected to alocal computer, e.g., in the form of a single-chip computer whichcontains or controls the control electronics. The component to becontrolled (switched) can then be controlled easily by the centralcomputer over the databus and by the local computers according to astandard protocol. The central computer has a client-server relationshipwith each of the local computers. Data exchange occurs between thecentral computer and the local computers via the databus in accordancewith the Internet protocol, and the networked computers define anintranet.

It is possible to assign a separate local computer to each individualelectric load. However, this means a relatively great expense for buslines and local computers. Since there is a growing trend today towardcombining multiple electric loads of related types or functions inprewired modules, according to a first embodiment of the presentinvention multiple electric loads are combined within a load module andcontrolled by a local computer. The databus may be designed to include aplurality of bus lines arranged in a star-shaped pattern between thecentral computer and the individual load modules, thus permitting easyassembly and easy expandability to add new modules or loads.

According to another preferred embodiment, the controller is especiallysimple and flexible if a server program, in particular a micro-serverprogram, is installed in the local computers and a browser program isinstalled in the central computer for the purpose of data exchange. Suchmicro-servers, which need only a few kB of memory and thus can run on asmall single-chip computer, have been available for some time and aremarketed by the American company Spyglass, for example.

Thus, it is possible to retrofit a motor vehicle with power windows, forexample, without causing the central computer to be underdimensioned asa result.

In addition, the CPU and the memory equipment of the central computermay be designed substantially independent of the electric equipment ofthe motor vehicle, which is advantageous in reducing inventories ofspare parts at the automotive manufactures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a first embodiment of a controlleraccording to the present invention.

FIG. 2 is a schematic diagram of a second embodiment of the controlleraccording to the present invention.

FIG. 3 is a flow chart of a control process in the control system thatdefines an intranet according to the present invention.

DETAILED DESCRIPTION

FIG. 1 shows a first embodiment of an automotive controller according tothe present invention. In controller 10, a central computer 11 locatedin or near the dashboard, for example, exchanges control data via acommon data bus 15 with individual local computers 19 and 22, each beingassigned to loads 20 or 23 within a load module 18 or 21. Load module 18may be, for example, a power window module, and load module 21 may be aseat adjuster. Computers 11, 19 and 22 are each connected to databus 15by connecting lines 14, 16 and 17. Both central computer 11 and loadmodules 18, 21 are supplied separately with battery power VB. AnInternet browser is run as an application program on central computer11. A micro-server is run as the application program on local computers19, 22. Each of the three units 11, 18, 21 has its own Internet address,e.g., “auto-pc.my-auto.car” or “powerwindowl.my-auto.car” and“seatl.my-auto.car.”

FIG. 3 shows a schematic diagram of the control sequence, where:

-   A=start browser-   B=server query-   C=server searches for previous home page-   D=browser shows previous status-   E=input of new status-   F=browser sends setpoint status-   G=server gives command to controller-   H=server sends new home page-   I=browser shows new status

To control the power windows, by analogy with the self-explanatorydiagram in FIG. 3, the web client is started on the central computer(“auto PC”) and the homepage of the power window (web server on localcomputer 19) is called up, for example. This presents the status andpermits changes to be made. This can be done, for example, by using aninput device (e.g., keyboard, etc.) 12 connected to central computer 11.Example: status displayed: “window open.” Action: closing the windowpartially with a “soft” linear regulator or completely with a “soft”pushbutton (the soft elements are operating elements produced anddisplayed by the software). Final status displayed: “window (partially)closed”.

In the case of the electrically adjustable seat load module 21), comfortfeatures such as a personal adjustment profile are also possible and maybe provided. These features may be controlled, called up and programmedover central computer 11. However, it is also possible to store the datafor this in load module (seat module) 21 itself as well as in centralcomputer 11.

If a display device 13 (e.g., a large-area LCD display) is connected tocentral computer 11, as shown in FIG. 1, the home pages of theindividual loads or load modules may in fact be represented graphically.However, this is not essential for the functioning of the controlleraccording to the present invention. Instead, the type of communicationusing a common (Internet) protocol and the allocation of the computerintelligence to central computer 11 as the client and local computers19, 22 as servers is important.

Essentially, the electric loads may all be designed individually asintelligent modules with a server function. However, it has becomeincreasingly a standard practice in the automotive industry to assemblea vehicle from individual modules that have been completely assembledand prewired in advance by subcontractors, e.g., the front section withthe headlight/turn signal combinations. In this regard, as illustratedin FIG. 2, individual electric loads 31, 32 and/or 35 and/or 38, 39which belong together functionally, are combined into prewired loadmodules 29 and/or 33 and/or 36 and controlled within the load module bya single local computer 30 or 34 or 37 as the local intelligence.Intelligent load modules 29, 33, 36 are connected over star-shaped buslines 26, 27, 28 to a central computer 25 which controls as a client thelocal computers/servers 30, 34, 37 according to the Internet protocol.Load modules 29 and 36 may be seat modules, for example, each with twomotors as electric loads 31, 32 or 39, 39. Load module 33 may be, forexample, a front module with six electric loads 35, each composed of twolamps, two turn indicators and two headlight height adjustments (threeloads each on the right and left).

Electric components loads 31, 32 and/or 35 and/or 38, 39 are prewired inload modules 29, 33, 36. A local computer 30 or 34 or 37 is included andwired as the module intelligence in each module. No plugs are needed. Tothe outside, each module has two connections, namely an electricconnection to the power supply and a bus line 26 or 27 or 28. Theelectric connection is connected to the battery power VB by any suitablemethod. The bus line (bus connection) is a cable, optionally long andwith an optional plug. Central computer 25 is arranged on the dashboard.On the rear side it has a number of bushings (not shown) into which buscables 26, 27, 28 from load modules 29, 33, 36 are inserted.

To adjust a seat, a command is sent from the central computer (e.g., inthe manner described above, see FIG. 3) over operating elements on thedashboard to seat module 29 where the local computer then controls thecorresponding motor (load 31 or 32). Likewise, to adjust a headlightfrom central computer 25 over operating elements on the dashboard, acommand is sent to headlight module 33, where local computer 34 controlsthe corresponding motor. To turn on a headlight, a command is sent fromcentral computer 25 over operating elements on the dashboard toheadlight module (front module) 33 where local computer 34 turns on thecorresponding headlight.

Since central computer 25 is not under any special load due to theswitching operations, it is expedient to use for this a computer that isalready present in the dashboard for other purposes (e.g.,infotainment).

The present invention provides an automotive controller which has asimple design, is expandable and flexible to use and can be implementedwith standardized hardware and software components.

1. A controller for a plurality of electric loads of a motor vehicle,comprising: a central computer; a databus; and a plurality of localcomputers, each local computer corresponding to and configured tocontrol a respective one of the electric loads, each local computerbeing connected to the central computer via the databus and beingconfigured to exchange control data according to an Internet protocolvia the databus; wherein each electric load is arranged with therespective local computer in one of a plurality of load modules and iscontrolled by the respective local computer within the load module;wherein the central computer is in a client-server relationship witheach of the local computers; and wherein the central computer and thelocal computers define an intranet; wherein each local computer includesa server program for the data exchange and wherein the central computerincludes a browser program.
 2. The controller according to claim 1,wherein one of the plurality of load modules includes a set of theelectric loads, the set of the electric loads being controlled by one ofthe local computers.
 3. The controller according to claim 2, wherein thedatabus includes a plurality of bus lines arranged in a star networkbetween the central computer and the load modules.
 4. The controlleraccording to claim 1, wherein the server program includes a micro-serverprogram.
 5. The controller according to claim 1, further comprising adisplay device connected to the central computer, the display devicebeing configured to display a home page of a respective one of the localcomputers selected for control.